Nitsch Engineering assisted the Philadelphia Water District to develop sewer separation strategies and green infrastructure concepts in Philadelphia’s Stadium District, a 600+-acre area that includes the stadiums and parking for Philadelphia’s professional sports teams (Citizens Bank Park, the Wells Fargo Center, and Lincoln Financial Field), as well a number of large industrial properties. This area is almost 100% impervious surface and the parking areas associated with the stadiums are drastically underutilized – generating significant amounts of stormwater runoff.
The project aimed to identify and implement strategies to help the City comply with a Consent Order Agreement with the Pennsylvania Department of Environmental Protection, under which they are required to eliminate stormwater discharges to their Combined Sewer system that ultimately flows to their wastewater treatment plants and at times the Delaware River. As a subconsultant, Nitsch Engineering assisted with this planning study by identifying Green Infrastructure Best Management Practices (GI BMPs) that could be implemented to collect stormwater prior to discharging to the combined sewer system and infiltrate it into the ground. The BMPs included green roofs, porous asphalt, porous pavers, bioretention planters, and underground infiltration trenches.
In addition to identifying potential locations for GI BMPs, Nitsch Engineering developed routing alternatives for new sewer and drain piping to separate stormwater and sanitary sewer out of the City’s combined sewer system. We relied on geotechnical information, existing flow patterns, land use, ground cover, and underground utility locations to determine the locations and preliminary sizing of GI BMPs. Nitsch Engineering prepared conceptual plans, sizing calculations, and cost estimates for the designs.